Prostate cancer is the most commonly diagnosed non-cutaneous neoplasm among males in Western countries and is estimated to result in 28,900 deaths this year in the U.S. alone. The advent of widespread PSA screening has resulted in increased detection of prostate cancer at earlier stages. A persistent and recalcitrant problem is that men with similar stage tumors often exhibit markedly different clinical outcomes following therapy, i.e. surgery or radiation. Early detection combined with slowly progressing tumors means a significant subset of men may be candidates for watchful waiting or active surveillance rather than treatment, and this will become increasingly important as the population ages. Thus, it is imperative that new methods be developed for patient stratification based on risk of recurrence to enable appropriate patient management.